<!DOCTYPE html>
<html lang="en" xmlns:th="http://www.thymeleaf.org"
      xmlns:sec="http://www.thymeleaf.org/thymeleaf-extras-springsecurity4">
<!-- th:fragment 定义需要引入的代码块，该div包含的内容即为引用的公共内容 -->
<!-- html底部 -->
<div th:fragment="footer">
    <footer class="sticky-footer bg-white" style="height: 20px">
        <div class="container my-auto">
            <div class="copyright text-center my-auto">
                <span>Copyright &copy; 2020</span>
            </div>
        </div>
        <!-- 将loading放在footer里 -->
        <div id="loading" style="display: none" class="my-center">
            <img src='../img/avatar/loading.gif' />
        </div>
    </footer>
</div>
</html>